Middle-class discontent and a self-confident, armed miners' movement brought on the 1952 Bolivian Revolution. This was only the second social revolution in Latin America and was led by the Revolutionary Nationalist Movement (MNR). In 1953 a radical land reform restored land to peasant communities that had lost out to big estates in the nineteenth and early twentieth centuries. The MNR government also nationalized the tin industry in 1952, and for a short period (until 1964), militias of tin workers and peasants displaced the traditional armed forces.
In 1964, a revitalized national army overthrew the MNR and ruled Bolivia with the help of a military-peasant pact that secured the neutrality of the rural masses and facilitated the army's repression of the militant leftist tin miners. The newly installed government of Rene Barrientos (1966–1969) defeated the insurrection headed by Che Guevara during the 1966–1967 period. The Guevarista effort to establish a revolutionary base, or foco, languished in the absence of peasant support. The traditional centers of the Bolivian Left—the tin miners, the Bolivian Workers Central, and the Bolivian Communist Party—remained on the margins or were actively hostile to Guevara's enterprise. Guevara was killed in 1967 by Bolivian Rangers trained by U.S. military advisors.
From the early 1970s to 1986 Bolivia was ruled by a bewildering series of governments that ranged from the moderate Left to the far Right. After 1986, civilian rule was maintained by a series of governments built around three political parties: the MNR, the Party of the Revolutionary Left (PIR), and the Nationalist Democratic Action (AND).
In the 1970s, coca, a traditional part of indigenous culture, became a hugely profitable commercial crop, leading to the corruption of the armed forces and political parties who profited from protecting growers and traffickers. The eradication of coca became the centerpiece of U.S. policy toward Bolivia from the 1980s onward. The United States demanded and financed the eradication of coca cultivation and made aid dependent on Bolivia's cooperation in this endeavor. The war on drugs was, in some ways, a replacement of the Cold War, and the sharply increased level of U.S. economic and military intervention in the war pitted the United States and its government allies against nationalist groups, especially the increasingly powerful peasant federations (such as the movement of the coca growers, or cocaleros, led by Evo Morales) that challenged the old social order from the 1980s.
Pressure from nationalist and anti-imperialist peasant and urban popular movements angered by the sale of state enterprises (water utilities and petroleum and gas companies) to foreign corporations destabilized governments in the 1990–1995 period. In the three years of 2002–2005, two elected presidents (Gonzalo Sánchez de Losada and Carlos Mesa) were forced to resign under pressure from mass urban and rural mobilizations.
Dunkerley, James. Rebellion in the Veins: Political Struggle in Bolivia, 1952–1982. London: Verso, 1984.